Diona Reasonover

Intro

Diona Reasonover is an American actor, writer and improviser known for playing forensic scientist Kasie Hines in NCIS. Her career brings together formal theater training, comedy, television writing and screen performance. NCIS is a useful entry point, but the series began long before she joined it: the 2003 date here identifies the production, while her arrival belongs to its later seasons. This guide follows the work behind that character and uses a credited portrait alongside selected production artwork to keep those distinctions clear.

Career snapshot

Reasonover was born in Detroit and studied theater and dance at Oberlin College before earning a master's degree in acting at the California Institute of the Arts. Paramount's biography also identifies comedy training with Upright Citizens Brigade and Second City. That combination places prepared performance and improvisation within the same professional background. It provides context for a career moving among scripted comedy, dramatic scenes and writing, without implying that every moment on screen is improvised or that a fictional character shares the actor's personal history.

The entry point

Reasonover appeared as Kasie during NCIS's fifteenth season and became a series regular for season sixteen. Contemporary TV Insider coverage documents that transition and the attention surrounding a new face in the laboratory. Kasie's forensic work makes her part of the process through which evidence becomes meaningful to the investigators. For a viewer meeting the character for the first time, the useful question is how she explains a discovery and responds to colleagues, rather than whether she duplicates the style of an earlier member of the cast.

Screen identity and style

In her early NCIS interviews, Reasonover discussed joining an established ensemble and developing Kasie as her own character. The setting gives her a recurring task: making technical information part of a human exchange. A rewatch can follow the change between a moment of enthusiasm, a joke and a more serious explanation. These are observations about how a scene can be approached, not claims about real forensic procedure. The surrounding cast matters because a laboratory scene still depends on listening, reaction and the relationship between the people in it.

Collaborations and patterns

Reasonover's work extends to writing, with Paramount listing credits on I Love You, America, I Love Dick, Adam Ruins Everything and NCIS. Her acting credits include Clipped, Grace and Frankie, Superstore and No Activity. The movement between writing and performance gives several ways to explore her career without treating them as interchangeable jobs. A writing credit identifies participation in creating a program; an acting credit identifies a performance within it. The gallery's Grace and Frankie image represents the production as a whole and is not presented as a portrait of Reasonover.

Era reflection

Periodic Talks, co-hosted with Gillian Jacobs, brought Reasonover into a conversational format focused on science and the people working in it. She discussed the podcast in an Earwolf appearance, while Paramount describes its attention to women and people of color in STEM, including historical figures. This is a useful counterpart to a fictional laboratory role, but the two should remain distinct. One uses a written character within a crime story; the other introduces real people and ideas through discussion. Neither format is simply an extension of the other.

Legacy and rediscovery

Reasonover and Brian Dietzen also co-host NCIS: Partners & Probies, bringing conversations with performers and other contributors to the franchise's audience. That work offers listeners another perspective on a series they may know through its characters. A useful starting route through her career combines a Kasie episode with an earlier comedy appearance and one of the interview formats. The sources below support the education, credits and chronology in this guide, while the viewing notes invite attention to the different demands of acting, writing and hosting.

A career in pictures

Selected career milestones. Years identify the production or labeled milestone; recurring actors may join a series later. Artwork represents the production and may show other cast members. Select an image for a larger view.

Rewatch notes

• Reasonover trained at Oberlin College and CalArts.
• She became an NCIS series regular in season sixteen.
• She co-hosted Periodic Talks with Gillian Jacobs.

Career highlights

NCIS (2003) as Kasie Hines
Series premiere year; Reasonover joined during season fifteen.

Grace and Frankie (2015) as Guest performer
Production artwork for one of her television comedy credits.