Weekend TV watch

Spend your Saturday night with Jennifer Lopez, Marc Anthony, Demi Lovato, Romeo Santos and more as a legion of stars come out for “Somos Live!” a three-hour telethon to support disaster relief efforts. The music starts at 8 p.m. in an unprecedented simultaneous broadcast on the Spanish channels Univision and Telemundo. NBC joins in for the third hour at 10 p.m. Watch and considering donating something to help your fellow Americans suffering in Puerto Rico.

Andra Day, Dionne Warwick, Dwight Yoakam and Valerie Simpson are just a few of the stars aligning for “Great Performances presents Grammy Salute to Music Legends 2017” (9 tonight on PBS), a concert spotlighting the music academy’s 2017 special merit awards recipients., including Shirley Caesar, Ahmad Jamal, Charley Pride and Sly Stone.

It’s a weekend to say goodbye to some beloved shows. On the two-hour conclusion of “Halt and Catch Fire” (9 p.m. tomorrow on AMC), our techies face an uncertain future. On the series finale of “Survivor’s Remorse” (10 p.m. Sunday on Starz), Cam is drawn to a risky investment and a surprising secret leads him to a professional crossroad. Oh, and there’s a long-awaited family engagement party.

Where is Dirk Gently? That’s the dire question as the second season of “Dirk Gently’s Holistic Detective Agency” opens (tomorrow at 9 p.m. on BBC America). Todd and Farah, running from the law, just happen to find refuge in a small Montana town filled with mystery. On this show, in this mad world, everything and everyone is connected.