Matt Passmore and Natalia Cigliuti Matt Passmore and Natalia Cigliuti

What's old is new again for Jim on The Glades.

On Sunday's episode, his ex-partner/ex-girlfriend Detective Samantha Harper (Natalie Cigliuti) drops by to track down the North Side Strangler, a serial killer that's been on the loose since their days on the beat together in Chicago. Jim (Matt Passmore) and Harper team up again, but will it remain all business — especially with Callie (Kiele Sanchez) in the picture now?

VIDEO: The Glades' Matt Passmore: There are a lot of obstacles between Jim and Callie

Get a first look at Harper's debut in the exclusive clips below, starting with her surprising a shirtless Jim at the pool:

Who wears the pants in this partnership? Jim and Harper make a small break in the case, but she tries to take charge:

The two finally discuss their romantic past that involves [spoiler alert!] an engagement:

The Glades airs Sundays at 10/9c on A&E.